1. Field of the Invention
The present invention relates to a pressurized gas circuit-breaker pole that can be assembled and disassembled without significant loss of gas and including a first enclosure or pole head including a first envelope including a first connecting flange including a circular orifice, said envelope containing a first mobile assembly terminating in a coupling member coaxial with said orifice, and a second enclosure constituting an insulative column including a second envelope including a second connecting flange including a circular orifice, said second envelope containing a second mobile assembly consisting of a link for maneuvering said first mobile assembly and its end including complementary means for coupling it with said coupling member.
2. Description of the Prior Art
The poles of large circuit-breakers, and in particular T-shaped poles with two interrupter chambers in series, cannot be transported to the installation site fully assembled: the head of the pole on the one hand, constituting a first enclosure containing all the active, fixed and mobile members of the two interrupter chambers, and the insulative column on the other hand, containing the link for maneuvering the mobile parts of the circuit-breaker pole, are therefore shipped in a disassembled state and assembled only on site.
It is necessary to evacuate the pole before filling it with a dielectric gas such as SF6. However, this operation requires a pump, which is not always available on site.
Also, this operation must be carried out in the manufacturing plant for each of the two parts of the pole: pole head and insulative column. Once the vacuum has been established, the two parts are filled with dielectric gas with an overpressure of the order of 0.3 bar and the parts are shipped to the site in this state. Once assembled, the gas pressure in the pole is set to its nominal value.
The problems therefore arise at assembly time of connecting the two enclosures and coupling the link to the coupling end of the mobile assembly without losing any gas or with minimum loss of gas and of providing gaseous communication between the two enclosures when assembly is complete.
The document FR-A1-2 568 405 describes a circuit-breaker in which the head of each pole includes a sliding airlock and the column includes a chimney, enabling coupling and decoupling with a small loss of gas corresponding to the combined volume of the airlock and the chimney. However, this necessitates several additional components, including the sliding airlock and a sliding jacket, as well as a special xe2x80x9cchimneyxe2x80x9d conformation of the end of the column. Also, an additional travel of the mobile parts of the pole, beyond the closed position of the circuit-breaker, must be provided for.
The document FR 2 415 358 A describes a circuit-breaker which enables, by virtue of an inflatable seal, transportation of the insulative support before its assembly with the upper part, the insulative support having first been evacuated then filled with gas. However, there is no provision for the upper part and, furthermore, it is necessary to deflate the seal of the insulative column after assembly.
An object of the present invention is to propose a simplified solution requiring only a few components and enabling fast assembly and disassembly and requiring no operation other than that of assembling and pressurizing the pole with dielectric gas to the nominal value, the gaseous communication between the two enclosures being automatic and not demanding any additional operation.
The invention therefore provides a pressurized gas circuit-breaker pole that can be assembled and disassembled without significant loss of gas and including a first enclosure or pole head including a first envelope including a first connecting flange including a circular orifice, the envelope containing a first mobile assembly terminating in a coupling member coaxial with the orifice, and a second enclosure constituting an insulative column including a second envelope including a second connecting flange including a circular orifice, the second envelope containing a second mobile assembly including a link for maneuvering the first mobile assembly and having an end including a complementary coupling member for coupling the end with the coupling member, wherein the connecting flange of each enclosure is fitted with an annular elastomer seal fixed to the corresponding connecting flange and through which the corresponding mobile assembly passes, the seal of each enclosure providing, during assembly of the flanges and coupling of the internal mobile assemblies, a sliding seal along the respective mobile assemblies, and means being provided to break the seal along the mobile assemblies on completion of assembly by reversible and automatic deformation of the annular elastomer seal to establish communication between the two enclosures.
In a first embodiment of the invention the annular elastomer seals are tilting deformable seals.
Each of the tilting deformable seals advantageously includes an external anchor ring connected by an isthmus to a seal body including a heel and a lip and the heel of each seal projects beyond the exterior plane of the corresponding flange.
In a second embodiment of the invention the means for breaking the seal along the mobile assemblies include a slide whose axial length is greater than the distance between the two annular elastomer seals in the assembled position of the first and second envelopes.
In a third embodiment of the invention each of the annular elastomer seals includes a first peripheral part gripped between a flange and a backing flange, a second part constituting a deformable hollow ring including walls with more flexible parts and more rigid parts, and a central third part constituting a simple thin disc providing the sliding seal along the mobile assembly.
A few embodiments of the invention will now be described with reference to the accompanying drawings.